Magnetic fluid (MF) seals have been used in air to seal vacuum devices or to protect equipment against dust intrusion. The performance of a MF seal, however, decreases in liquids, often because the magnetic fluid is exposed to the flow field and can be carried away by the liquid the seal is designed to operate in. To our knowledge, a MF seal for use in blood or similar liquids that overcomes such leaking issues, which may lead to clotting blood interfering with normal pump operation, has not yet been developed.
A miniature MF seal that is capable of operating when submerged in a liquid such as blood is discussed further herein.